JP5646017B2 - Relay communication method and device - Google Patents

Description

  Various embodiments relate to wireless communications, and more particularly, to methods and apparatus for using relay stations.

  In cellular networks with relay stations, for example cellular networks implementing 802.16J, a common implementation is to configure time division multiplexing between different types of traffic. For example, the downlink slot is divided into three types: base station to relay station, relay station to mobile station, and base station to mobile station, and a single logical sequence of downlink slots traverses across the cells of the network. It is done.

  This approach of using a common slot allocation method throughout the system is problematic especially in the border area from the point of view of interference. For example, when two neighboring cells are transmitting data from the relay station to the mobile station at the same time, the mobile stations in the cell boundary region can be expected to experience inter-cell interference, and the signal-to-interference noise ratio ( SINR) may decrease.

  Based on the above discussion, there is a need for new methods and devices that mitigate interference in wireless communication systems that use relay stations.

  Various embodiments are directed to methods and apparatus useful for reducing interference in wireless communication systems including multi-sector base stations and relay stations. In certain embodiments, an exemplary wireless communication system uses a plurality of different types of transmission slots including a base station-relay station slot, a relay station-access terminal slot, and a base station-access terminal slot. The exemplary wireless communication system further implements a plurality of different slot type allocation sequences in the system, eg, two different slot type allocation sequences. Different slot type allocation sequences are sometimes referred to as schedules. In one embodiment, the two different slot type sequences differ in that the first sequence of relay station-access terminal slots does not overlap with the second sequence of relay station-access terminal slots. An arrangement pattern is implemented in the system that associates each particular base station sector and its associated relay station with one of the different slot type sequences. In at least some multi-sector base stations in the system, different sectors intentionally use different slot type allocation sequences. When an access terminal in the system determines a slot type allocation sequence corresponding to a base station sector or relay station from which it intends to receive downlink signals, and communicates with that particular base station sector or relay station, Use the determined slot type sequence.

  By using a plurality of slot type allocation sequences and implementing an arrangement arrangement that is advantageous in the system, the interference experienced by the access terminal in the boundary region can be reduced.

  An exemplary method of operating a sectorized communication device, eg, a sectorized base station, according to an embodiment includes transmitting from the first sector of the communication device to a first relay station during a first time interval, and a second time interval. Transmitting from the second sector of the communication device to the second relay station, including the time interval in which the first time interval and the second time interval do not overlap. A sectorized communication device according to an embodiment transmits from a first sector of the communication device to a first relay station during a first time interval and from a second sector of the communication device to a second relay station during a second time interval. At least one processor configured to be a time interval in which the first time interval and the second time interval do not overlap. The exemplary sectored communication device further includes a memory coupled to the at least one processor.

  An exemplary method of operating an access terminal according to an embodiment is to communicate with a first access point according to a first schedule, wherein the first schedule includes an access point-access terminal communication time slot, the first Performing a handoff to a second access point that is synchronized with one access point, and communicating with a second access point according to a second schedule, wherein the second schedule includes an access point-access terminal communication time slot Including that the access point-access terminal communication time slot in the first schedule does not overlap with the access point-access terminal communication time slot in the second schedule. In some such embodiments, the access point is a relay station and the access point-access terminal time slot is a relay station-access terminal time slot.

  In an embodiment, an exemplary access terminal communicates with a first access point according to a first schedule, wherein the first schedule includes an access point-access terminal communication time slot and is synchronized with the first access point. Performing a handoff to an access point, communicating with a second access point according to a second schedule, wherein the second schedule includes an access point-access terminal communication time slot, and the access point-access terminal time slot in the first schedule Comprises at least one processor configured not to overlap with an access point-access terminal time slot in the second schedule. The exemplary access terminal further comprises a memory coupled to the at least one processor.

  While various embodiments have been discussed in the summary above, not all embodiments include the same functionality, and some embodiments may not require some of the features described above, but may be desirable. I want you to understand. Numerous additional features, embodiments, and advantages of various embodiments are discussed in the detailed description that follows.

1 is a drawing of an example wireless communication system including a multi-sector base station, a relay station, and an access terminal, according to an example embodiment. 2 is a flowchart of an exemplary method of operating a sectorized communication device in a wireless communication system. 1 is a drawing of an example sectorized communication device according to an example embodiment. FIG. 4 is an assembly of modules that can be used in the sectored communication device shown in FIG. 3 and used in certain embodiments. FIG. 2 is a flow diagram of an example method of operating an access terminal in a wireless communication system. 2 is a drawing of an exemplary access terminal according to an exemplary embodiment. 7 is an assembly of modules that can be used in the access terminal shown in FIG. 6 and used in certain embodiments. 6 is a diagram illustrating different exemplary slot type allocation schedules according to exemplary embodiments. FIG. 3 illustrates an exemplary slot type allocation pattern across a multi-cell communication system, according to an exemplary embodiment. FIG. 10 illustrates an exemplary embodiment in which the slot type allocation of FIG. 8 and the arrangement pattern of FIG. 9 are used in the exemplary system of FIG. FIG. 6 illustrates different exemplary slot type allocation schedules according to another exemplary embodiment. FIG. 6 illustrates different exemplary slot type allocation schedules according to yet another exemplary embodiment.

  FIG. 1 is a drawing of an exemplary wireless communication system 100 in accordance with an exemplary embodiment. Exemplary wireless communication system 100 includes a plurality of multi-sector base stations (base station 1102, base station 2104, ... base station N106). Exemplary base stations (102, 104,..., 106) are coupled to each other via backhaul network 107 and to other network nodes and / or the Internet.

  The exemplary communication system 100 also includes a plurality of relay stations (RS1 126, RS2 128, RS3 130, RS4 132, RS5 134, RS6 136, RS7 138, RS8 140, ..., RSN that extend the coverage area of the base station. 142). In this example, the relay station has a corresponding base station sector. Specifically, the relay stations (RS1 126, RS2 128, RS3 130, RS4 132, RS5 134, RS6 136, RS7 138, RS8 140, ..., RSN 142) are respectively base station-sector (base station 1 Sector 1 108, base station 1 sector 2 110, base station 1 sector 3 112, base station 2 sector 1 114, base station 2 sector 2 116, base station 2 sector 3 118, base station N sector 1 120, base station N sector 2 122, base station N sector 3 124).

  The exemplary communication network 100 also includes multiple access terminals (AT1 144, AT2 146, AT3 148, AT4 150, AT5 152, AT6 154, AT7 156, AT8 158, AT9 160, AT10 162, AT11 164, AT12 166, AT13 168, AT14 170, AT15 172, AT16 174, AT17 176, AT18 178, AT19 180, ..., ATN 182), including wireless terminals, for example. At least some of the access terminals are mobile wireless terminals that can move throughout the communication system 100 and have different connection points at different times depending on their current location.

  In this example, the access terminal (AT1 144, AT2 146, AT3 148, AT4 150, AT5 152, AT6 154, AT7 156, AT8 158, AT9 160, AT10 162, AT11 164, AT12 166, AT13 168, AT14 170, AT15 172, AT16 174, AT17 176) are (RS1 126, BS1 sector 1 108, BS1 sector 2 110, RS2 128, RS3 130, BS1 sector 3 112, BS2 sector 1 114, RS4 132, RS5 134, BS2 sector 2 respectively. 116, RS6 136, BS2 sector 3 118, BSN sector 1 120, RS7 138, BSN sector 2 122, RS8 140, RSN 142, BSN sector 3 124). Access terminal 19 180 is in the process of a handoff between RS8 140 and RSN 142, which is a handoff between adjacent relay stations corresponding to the same base station. Access terminal N182 is in the process of handoff between RSN 142 and RS4 132, which is a handoff between adjacent relay stations corresponding to different base stations.

  FIG. 2 is a flowchart 200 of an exemplary method of operating a sectorized communication device according to an exemplary embodiment. The sectorized communication device is a communication device including a plurality of sectors, for example, at least a first sector and a second sector. In one embodiment, the sectored communication device includes three sectors. The sectorized communication device is, for example, a sectorized base station. For example, the sectorized communication device is one of the sectorized base stations of the system 100 of FIG. Operation begins at step 202 where the sectored communication device is powered on and initialized and proceeds to step 204. Steps 206 and 208 are optional steps, and in some embodiments, include one or more of them. In certain such embodiments, operation also proceeds from step 202 to one or more of optional steps 206 and 208.

  In step 204, the communication device transmits from the first sector of the communication device to the first relay station during the first time interval. Returning to step 206, in step 206, the communication device is controlled to refrain from transmitting from the second sector during the first time interval. Returning to step 208, in step 208, the communication device transmits from the third sector of the communication device to the third relay station during the first time interval. Operation proceeds from step 204 to step 210. In certain embodiments, operation further proceeds to step 210 from one or more of steps 206 and 208.

  In step 210, the communication device transmits from the second sector of the communication device to the second relay station during the second time interval, and the first time interval and the second time interval are non-overlapping time intervals. In various embodiments, the first time interval and the second time interval are circulating time intervals. In an embodiment, the first time interval is a time interval that the second relay station transmits to the access terminal. In an embodiment, the first time interval is a time interval that the first relay station transmits to the access terminal.

  In various embodiments, the first and second relay stations are relay stations corresponding to the first and second sectors, respectively. In some such embodiments, the third relay station corresponds to the third sector.

  Operation proceeds from step 210 to step 212. In step 212, the communication device transmits simultaneously from the first and second sectors to the access terminal. In some such embodiments, the communication device transmits simultaneously to its access terminal from its respective sector, eg, the first, second, and third sectors. Operation proceeds from step 212 to the input of step 204. In certain embodiments, operation also proceeds from step 212 to one or more inputs of steps 206 and 208.

  FIG. 3 is a drawing of an example sectorized communication device 300, eg, a sectorized base station, according to an example embodiment. The communication device 300 is, for example, one of the base stations of the system 100 in FIG. The example sectorized communication device 300 implements the method according to the flowchart 200 of FIG.

  The communication device 300 includes a processor 302 and a memory 304 coupled to each other via a bus 309, and various elements (302, 304) can exchange data and information via the bus 309. The communication device 300 further includes an input module 306 and an output module 308, which can be coupled to the processor 302, as shown. However, in some embodiments, input module 306 and output module 308 are located within processor 302. The input module 306 can receive an input signal. The input module 306 can include a wireless receiver that receives input and / or a wired input interface or an optical input interface, and in certain embodiments includes them. In some embodiments, input module 306 includes individual input submodules corresponding to each sector of sectored communication device 300. The output module 308 can include a wireless transmitter that transmits the output and / or a wired output interface or an optical output interface, which in some embodiments includes them. In certain embodiments, output module 308 includes individual output submodules corresponding to each sector of sectored communication device 300.

  The processor 302 transmits from the first sector of the communication device to the first relay station during a first time interval, transmits from the second sector of the communication device to the second relay station during a second time interval, and The first time interval and the second time interval are configured to be non-overlapping time intervals. In various embodiments, the first time interval and the second time interval are circulating time intervals. In one embodiment, the second time interval is a time interval at which the first relay station transmits to an access terminal. In one embodiment, the first time interval is a time interval at which the second relay station transmits to an access terminal. In one embodiment, the first and second relay stations are relay stations corresponding to the first and second sectors, respectively.

  In an embodiment, the processor 302 is further configured to transmit simultaneously from the first and second sectors to the access terminal. In an embodiment, the processor 302 is configured to refrain from transmitting from the second sector during the first time interval.

  In certain embodiments, the sectored communication device of which processor 302 is a part includes three sectors, and processor 302 further transmits from the third sector of the communication device to a third relay station during a first time interval. Configured to do.

  FIG. 4 is an assembly 400 of modules that may be used with the sectored communication device 300 shown in FIG. 3, and in one embodiment. Modules in assembly 400 may be implemented as hardware in processor 302 of FIG. 3, for example, as individual circuits. Alternatively, the module can be implemented as software and stored in the memory 304 of the communication apparatus 300 shown in FIG. Although illustrated in the embodiment of FIG. 3 as a single processor, such as a computer, it should be understood that the processor 302 may be implemented as one or more processors, such as a computer. When implemented as software, the module includes code that, when executed by the processor, configures the processor, eg, computer 302, to implement functionality corresponding to the module. In an embodiment where the assembly 400 of modules is stored in the memory 304, the memory 304 includes code that causes at least one computer, eg, the processor 302, to implement the functions that the module corresponds to, eg, a computer that includes individual code for each module. A computer program product including a readable medium.

  Fully hardware based modules or fully software based modules can be used. However, it should be understood that functions can be implemented using any combination of software modules and hardware (eg, implemented in a circuit) modules. It should be understood that the modules shown in FIG. 4 control and / or configure elements such as communication device 300 or processor 302 therein, and the functionality of the corresponding steps shown in method flow diagram 200 of FIG. To implement.

  As shown in FIG. 4, the assembly 400 of modules includes a module 404 that transmits from the first sector of the communication device to the first relay station during the first time interval, and a transmission from the second sector during the first time interval. A module 406 that refrains from transmission, a module 408 that transmits from the third sector of the communication device to the third relay station during the first time interval, and a second sector of the communication device that transmits from the second sector of the communication device to the second relay station during the second time interval. A module 410 for transmitting, the module 410 being a time interval in which the first time interval and the second time interval do not overlap, and a module 412 for simultaneously transmitting from the first and second sectors to the access terminal.

  In some embodiments, the first and second time intervals are circulating time intervals. In various embodiments, the first time interval is the time interval that the second relay station transmits to the access terminal. In an embodiment, the second time interval is a time interval that the first relay station transmits to the access terminal. In an embodiment, the first and second relay stations are relay stations corresponding to the first and second sectors, respectively.

  FIG. 5 is a flowchart 500 of an exemplary method of operating an access terminal, eg, a mobile node of a mobile terminal, according to an exemplary embodiment. An access terminal is part of a wireless communication system that includes, for example, sectorized base stations and relay stations. For example, the access terminal is one of the access terminals of the system 100 of FIG. Operation of the exemplary method begins at step 502 where the access terminal is powered on and initialized and proceeds to step 504.

  In step 504, the access terminal communicates with a first access point according to a first schedule, the first schedule including an access point-access terminal communication time slot. Operation proceeds from step 504 to step 506. In step 506, the access terminal determines a second schedule from the identifier corresponding to the second access point and the stored schedule information. In some embodiments, the determination is performed based on a combination of a device identifier and a sector identifier corresponding to the second access point. In some embodiments, the access terminal determines a device identifier and / or sector identifier from the received detected broadcast signal. In some such embodiments, the received broadcast signal is a beacon signal. Operation proceeds from step 506 to step 508. In step 508, the access terminal performs a handoff to a second access point that is synchronized with the first access point. In some embodiments, the first and second access points are adjacent relay stations. Then, in step 510, the access terminal communicates with a second access point according to a second schedule, wherein the second schedule includes an access point-access terminal communication time slot, and the access point-access terminal in the first schedule The time slot does not overlap with the access point-access terminal time slot in the second schedule.

  In an embodiment, the access point-access terminal time slot in the second schedule is a relay station-access terminal time slot, and the second schedule further includes a base station-relay station time slot. In some such embodiments, the second schedule further includes a base station-access terminal time slot. In some such embodiments, the access point-access terminal time slot in the first schedule is a relay station-access terminal time slot, and the first schedule is base station-relay station time slot and base station-access terminal time slot. It further includes a slot.

  FIG. 6 is a drawing of an exemplary access terminal 600, eg, a mobile wireless terminal, according to an exemplary embodiment. Access terminal 600 is, for example, one of the access terminals of system 100 of FIG. The example access terminal 600 implements the method according to the flowchart 500 of FIG.

  Access terminal 600 includes a processor 602 and a memory 604 coupled to each other via a bus 609, and various elements (602, 604) can exchange data and information via the bus 609. Access terminal 600 further includes an input module 606 and an output module 608, which can be coupled to processor 602 as shown. However, in certain embodiments, input module 606 and output module 608 are located within processor 602. The input module 606 can receive input signals and the output module 608 can transmit output signals. The input module 606 can include a wireless receiver that receives input and / or a wired input interface or an optical input interface, and in certain embodiments includes them. The output module 608 can include a wireless transmitter that transmits the output and / or a wired output interface or an optical output interface, which in some embodiments includes them.

  The processor 602 communicates with a first access point according to a first schedule, wherein the first schedule includes an access point-access terminal communication time slot and performs a handoff to a second access point that is synchronized with the first access point Communicating with a second access point according to a second schedule, wherein the second schedule includes an access point-access terminal communication time slot, and the access point-access terminal time slot in the first schedule is in the second schedule Access points—configured to not overlap with the access terminal time slot. In one embodiment, the first and second access points are adjacent relay stations. In some such embodiments, the access point-access terminal time slot is a relay station-access terminal time slot.

  In certain embodiments, the processor 602 is further configured to determine a second schedule from an identifier corresponding to the second access point and stored schedule information. In various embodiments, the access point-access terminal time slot in the second schedule is a relay station-access terminal time slot, and the second schedule further includes a base station-relay station time slot. In certain such embodiments, the second schedule further includes a base station-access terminal time slot. In some such embodiments, the first schedule includes a relay station-access terminal time slot, a base station-relay station time slot, and a base station-access terminal time slot.

  FIG. 7 is an assembly 700 of modules that may be used with the access terminal 600 shown in FIG. 6, and in one embodiment used. Modules in assembly 700 may be implemented as hardware in processor 602 of FIG. 6, for example, as individual circuits. Alternatively, the module can be implemented as software and stored in the memory 604 of the access terminal 600 shown in FIG. Although illustrated in the embodiment of FIG. 6 as a single processor, such as a computer, it should be understood that the processor 602 can be implemented as one or more processors, such as a computer. When implemented as software, the module includes code that, when executed on the processor, configures the processor 602, eg, a computer, to implement functionality corresponding to the module. In embodiments where the assembly 700 of modules is stored in the memory 604, the memory 604 includes code that causes at least one computer, eg, the processor 602, to implement the functions that the module corresponds to, eg, a computer that includes individual code for each module A computer program product including a readable medium.

  Fully hardware based modules or fully software based modules can be used. However, it should be understood that functions can be implemented using any combination of software modules and hardware (eg, implemented in a circuit) modules. It should be understood that the modules shown in FIG. 7 control and / or configure elements such as communication device 600 or processor 602 therein to function in corresponding steps shown in method flow diagram 500 of FIG. To implement.

  As shown in FIG. 7, an assembly 700 of modules is a module 704 that communicates with a first access point according to a first schedule, wherein the first schedule includes an access point-access terminal time slot; A module 706 for determining a second schedule from an identifier corresponding to two access points and stored schedule information; a module 708 for performing a handoff to a second access point synchronized with the first access point; and a second schedule In accordance with the second access point, wherein the second schedule includes an access point-access terminal communication time slot, and the access point-access terminal time slot in the first schedule is the second schedule Access point And a module 710 that does not overlap with Seth terminal time slots.

  In some embodiments, the first and second access points are adjacent relay stations. In various embodiments, the access point-access terminal time slot in the second schedule is a relay station-access terminal time slot, and the second schedule further includes a base station-relay station time slot. In some such embodiments, the second schedule further includes a base station-access terminal time slot. In some such embodiments, the first schedule includes a relay station-access terminal time slot, a base station-relay station time slot, and a base station-access terminal time slot.

  In an embodiment, module 706 performs the determination based on a combination of device identifier and sector identifier corresponding to the second access point. In some embodiments, the access terminal determines a device identifier and / or sector identifier from the received detected broadcast signal. In some such embodiments, the received broadcast signal is a beacon signal.

  FIG. 8 is a drawing 800 illustrating different example slot type allocation scheduling, according to an example embodiment. Drawing 800 includes a vertical axis 802 representing slot type allocation and a horizontal axis 804 representing time. Slot type allocation A806 is indicated by the pattern of base station-relay station slot 810, relay station-access terminal slot 812, and base station-access terminal slot 814. The scheduling pattern repeats as indicated by the following base station-relay station slot 816, relay station-access terminal slot 818, and base station-access terminal slot 820 sequence. Slot type allocation B808 is indicated by the pattern of relay station-access terminal slot 822, base station-relay station slot 824, and base station-access terminal slot 826. The scheduling pattern repeats as indicated by the following relay station-access terminal slot 828, base station-relay station slot 830, and base station-access terminal slot 832 sequence.

  Note that the relay station-access terminal slot corresponding to slot type A allocation does not intentionally overlap with the relay station-access terminal slot corresponding to slot type B allocation. This feature of non-overlapping relay station-access terminal time slots corresponding to different scheduling types is beneficial for interference mitigation.

  An example will be described to illustrate the benefits of techniques that mitigate interference using different types of downlink slot type allocation. Assume that the base station signal is received at the access terminal 10 dB higher than thermal and the relay station signal can be received at the access terminal 15 dB higher than heat. When every cell uses the same slot structure, the SINR recognized by the access terminal on the cell boundary is 0 dB due to interference from the relay station in the neighboring cell. On the other hand, when different slot types are used in two neighboring cells, since the interference is from neighboring BSs, the SINR recognized by the access terminal on the border cell is 5 dB at the worst.

  In the example of FIG. 8, it can also be observed that the base station-access terminal slot of slot type allocation A overlaps with the base station-access terminal slot of slot type allocation B. If an access terminal close to the base station is served by a base station rather than a relay station, the output level of the base station-access terminal signal is controlled, and inter-cell interference is a problem for overlapping base station-access terminal slots. It can be made low enough so that it does not become.

  FIG. 9 includes a drawing 900 illustrating an exemplary slot type allocation across a multi-cell communication system, according to an exemplary embodiment. In this example, there are two types of slot allocation used in the exemplary sectored arrangement. A sectored arrangement can include both sectorized base stations and relay stations, and in some cases both. Legend 902 shows that (i) “0” in drawing 900 represents a slot type allocation A for a base station sector and a relay station corresponding to the base station sector, and (ii) “1” in drawing 900 represents a base station Shows the slot type allocation B for relay stations corresponding to sectors and base station sectors. The slot allocation type A is, for example, the slot type allocation A806 shown in FIG. 8, and the slot type allocation B is, for example, the slot type allocation B808 shown in FIG.

  FIG. 10 is a drawing 1000 illustrating an exemplary embodiment in which the slot type allocation described in FIG. 8 and the arrangement pattern of FIG. 9 are used in the exemplary system 100 of FIG. Base station 1 sector 1 102 and corresponding relay station RS1 126 use slot allocation type B. The base station 1 sector 2110 and the corresponding relay station RS2 128 use the slot allocation type A. Base station 1 sector 3 112 and its corresponding relay station RS3 130 use slot allocation type B. The base station 2 sector 1 114 and the corresponding relay station RS4 132 use slot allocation type A. The base station 2 sector 2 116 and the corresponding relay station RS5 134 use slot allocation type B. Base station 2 sector 3 118 and its corresponding relay station RS6 136 use slot allocation type A. Base station N sector 1 120 and its corresponding relay station RS7 138 use slot allocation type B. The base station N sector 2 122 and the corresponding relay station RS8 140 use slot allocation type A. Base station N sector 3 124 and its corresponding relay station RSN 142 use slot allocation type B. An access terminal that communicates with a base station sector or relay station, eg, receives a downlink signal from the base station sector or relay station, determines a slot allocation type corresponding to the base station sector or relay station, and uses the determined schedule .

  FIG. 11 is a drawing 1100 illustrating different example slot type allocation scheduling, according to an example embodiment. In some embodiments, the different exemplary slot type allocation scheduling of FIG. 11 is used as an alternative to the exemplary slot type allocation of FIG. Drawing 1100 includes a vertical axis 1102 representing slot type allocation and a horizontal axis 1104 representing time. Slot type allocation A1106 is indicated by the pattern of base station-access terminal slot 1110, relay station-access terminal slot 1112, and base station-relay station slot 1114. The scheduling pattern repeats as indicated by the following base station-access terminal slot 1116, relay station-access terminal slot 1118, and base station-relay station slot 1120 sequences. Slot type allocation B1108 is indicated by the pattern of relay station-access terminal slot 1122, base station-relay station slot 1124, and base station-access terminal slot 1126. The scheduling pattern repeats as shown by the following relay station-access terminal slot 1128, base station-relay station slot 1130, and base station-access terminal slot 1132 sequence.

  Note that the relay station-access terminal slot corresponding to slot type A allocation does not intentionally overlap with the relay station-access terminal slot corresponding to slot type B allocation. This feature of non-overlapping relay station-access terminal time slots corresponding to different scheduling types is beneficial for interference mitigation.

  FIG. 12 is a drawing 1200 illustrating different example slot type allocation scheduling, according to an example embodiment. In some embodiments, the different exemplary slot type allocation scheduling of FIG. 12 is used as an alternative to the exemplary slot type allocation of FIG. Drawing 1200 includes a vertical axis 1202 representing slot type allocation and a horizontal axis 1204 representing time. Slot type allocation A1206 is indicated by the pattern of base station-relay station slot 1210, relay station-access terminal slot 1212, and base station-access terminal slot 1214. The scheduling pattern repeats as indicated by the following base station-relay station slot 1216, relay station-access terminal slot 1218, and base station-access terminal slot 1220 sequence. Slot type allocation B1208 is indicated by the pattern of relay station-access terminal slot 1222, base station-relay station slot 1224, and base station-access terminal slot 1226. The scheduling pattern repeats as shown by the following relay station-access terminal slot 1228, base station-relay station slot 1230, and base station-access terminal slot 1232 sequence. Slot type allocation C1209 is indicated by the pattern of base station-access terminal slot 1234, base station-relay station slot 1236, and relay station-access terminal slot 1238. The scheduling pattern repeats as indicated by the following base station-access terminal slot 1240, base station-relay station slot 1242, and relay station-access terminal slot 1244 sequence.

  The relay station-access terminal slot corresponding to slot type A allocation does not intentionally overlap with the relay station-access terminal slot corresponding to slot type B allocation, and there is no relay station-access terminal slot corresponding to slot type A allocation. Note that there is no intentional overlap with the relay station-access terminal slot corresponding to slot type C allocation. Further, the relay station-access terminal slot corresponding to slot type B allocation does not intentionally overlap with the relay station-access terminal slot corresponding to slot type C allocation. This feature of non-overlapping relay station-access terminal time slots corresponding to different scheduling types is beneficial for interference mitigation.

  In an embodiment, each of the different slot type allocations (A, B, C) is used in at least one sector of the multi-sector base station and its associated relay station. In some embodiments, multiple multi-sector cells in a communication system use the same mapping between slot type allocation and sector, eg, according to a predetermined pattern. In some embodiments, at least some different cells have different mappings between sectors and slot type allocation, eg, according to a predetermined pattern.

  Various embodiments of the techniques may be implemented using software, hardware, and / or a combination of software and hardware. Various embodiments are directed to devices, eg, mobile nodes such as relay stations, mobile access terminals, base stations including one or more connection points, and / or communication systems. Various embodiments are also directed to methods, eg, methods for controlling and / or operating relay stations, mobile nodes, base stations, and / or communication systems, eg, hosts. Various embodiments are also directed to a machine, eg, a computer, a readable medium containing machine readable instructions that control the machine to implement one or more steps of the method, eg, ROM, RAM, CD, hard disk, etc. To do.

  It should be understood that the specific order or hierarchy of steps in the processes disclosed is an example of an exemplary approach. It should be understood that a particular order or hierarchy of steps in the process can be reconfigured based on design preferences while remaining within the scope of this disclosure. The accompanying method claims the current elements of the various steps in the sample order and is not meant to be limited to the specific order or hierarchy presented.

  In various embodiments, a node described herein uses one or more modules to correspond to one or more methods, e.g., at a first time interval of the communication device. Transmission from one sector to the first relay station, transmission from the second sector of the communication device to the second relay station during the second time interval, and the first time interval and the second time interval overlap It is implemented so that it is not a time interval. Thus, in certain embodiments, various functions are implemented using modules. Such a module can be implemented using software, hardware, or a combination of software and hardware. Many of the methods or method steps described above can be implemented using machine-executable instructions such as software contained in a machine-readable medium such as a memory device, eg, RAM, floppy disk, etc. And control all or each part of the method described above, for example as one or more nodes. Accordingly, among other things, the various embodiments are directed to machine-readable media comprising machine-executable instructions that cause a machine, eg, a processor and associated hardware, to perform one or more of the steps of the method (s) described above. And Certain embodiments are directed to an apparatus, eg, a communication apparatus, that includes a processor configured to implement one, more than one, or all of the one or more method steps of the present invention.

  Certain embodiments are directed to a computer program product comprising a computer or computer readable medium comprising code that causes a plurality of computers to implement various functions, steps, operations, and / or operations, eg, one or more of the steps described above. And Depending on the embodiment, the computer program product may include various codes for performing each step, and in some cases. Thus, a computer program product can include code for each individual step of a method, eg, a method for controlling a communication device or node, and in some cases. The code may be in the form of machine-executable instructions, such as computer-executable instructions, stored on a computer-readable medium such as RAM (Random Access Memory), ROM (Read Only Memory), or other type storage devices. In addition to directed to a computer program product, an embodiment implements one or more of the various functions, steps, operations, and / or operations of one or more of the methods described above. For configured processors. Accordingly, certain embodiments are directed to a processor, eg, a CPU, configured to implement some or all of the method steps described herein. The processor may be for use with, for example, a communication device or other device described herein.

  In certain embodiments, one or more devices, e.g., processor (s) of a communication device such as a relay station, base station, or wireless terminal, e.g., a CPU, are described as being implemented by the communication device. Configured to perform the steps. Accordingly, some, but not all embodiments, are directed to an apparatus, eg, a communication apparatus, that includes a processor that includes modules corresponding to the steps of the various described methods performed by the apparatus that includes the processor. In some but not all embodiments, an apparatus, eg, a communication apparatus, includes modules that correspond to the steps of the various described methods performed by an apparatus that includes a processor. Modules can be implemented using software and / or hardware.

  Although described in the context of an OFDM system, at least some of the methods and apparatus of the various embodiments are applicable to a wide variety of communication systems including multiple non-OFDM and / or non-cellular systems. At least some of the methods and equipment are applicable to hybrid systems, such as systems that include OFDM and CDMA signaling techniques.

  In view of the above description, numerous additional variations on the methods and apparatus of the various embodiments described above will be apparent to those skilled in the art. Such variations are to be considered within the scope of the present disclosure. The method and apparatus are CDMA, orthogonal, which can be used to implement a wireless communication link between an access node and a mobile node, between an access node and a relay station, and / or between a relay station and a mobile node. It can be used with frequency division multiplexing (OFDM), and / or various other types of communication techniques, and in various embodiments, used with them. In some embodiments, the access node is implemented as a base station that establishes a communication link with the mobile node and / or relay station using OFDM and / or CDMA. In various embodiments, a mobile node is implemented as a notebook computer, personal digital assistant (PDA), or other portable device that includes a receiver / transmitter circuit and logic and / or routines to implement the method. The

100 wireless communication system
102 Base station 1
104 Base station 2
106 Base station N
107 Backhaul network
108 Base station 1 Sector 1
110 Base station 1 sector 2
112 Base station 1 sector 3
114 Base station 2 Sector 1
116 Base station 2 Sector 2
118 Base station 2 Sector 3
120 Base station N sector 1
122 Base station N sector 2
124 Base station N sector 3
126 Relay station RS1
128 Relay station RS2
130 Relay station RS3
132 Relay station RS4
134 Relay station RS5
136 Relay station RS6
138 Relay station RS7
140 Relay station RS8
142 RSN
144 Access terminal AT1
146 Access terminal AT2
148 Access terminal AT3
150 access terminal AT4
152 Access terminal AT5
154 Access terminal AT6
156 Access terminal AT7
158 Access terminal AT8
160 Access terminal AT9
162 Access terminal AT10
164 Access terminal AT11
166 Access terminal AT12
168 Access terminal AT13
170 Access terminal AT14
172 Access terminal AT15
174 Access terminal AT16
176 Access terminal AT17
178 Access terminal AT18
180 Access terminal AT19
182 Access terminal ATN
300 Sectorized communication equipment
302,602 processors
304,604 memory
306,606 input module
308,608 output module
309,609 bus
400,700 assembly
404,406,408,410,412,704,706,708,710 modules
600 access terminal
806,1106,1206 Slot type allocation A
808, 1108, 1208 Slot type allocation B
1209 Slot type allocation C
810,816,824,830,1114,1120,1124,1130,1210,1216,1224,1230,1236,1242 Base station-relay station slot
812,818,822,826,828,832,1112,1118,1122,1128,1212,1218,1222,1228,1238,1244 Relay station-access terminal slot
814,820,1110,1116,1126,1132,1214,1220,1226,123212341240 Base station-access terminal slot

Claims (15)

A method of operating an access terminal,
Comprising the steps of communicating with the first access point in accordance with a first schedule for use by the first access point, first the first base station including the first N pieces of sector access point is directed in different directions Located in a location adjacent to a sector, the first base station uses less than N schedules to control transmissions from the N sectors of the first base station, and the first schedule is less than N The first schedule is used to control transmissions from at least two adjacent sectors of the first base station , and the first schedule is a first base station-access terminal communication Including a first communication time slot repeating periodic sequence including a time slot, a first relay station-access terminal communication time slot, a first base station-relay station communication time slot ;
Performing a handoff to a second access point that is synchronized with the first access point;
Comprising the steps of communicating with the second access point according to a second schedule that is used by the second access point, wherein the second schedule RS2 - access terminal communications time slots, the second base station - repeater station communication time A second communication station comprising a slot, a second base station-access terminal communication time slot, and a repeating periodic sequence , wherein at least some communication time slots in the first schedule are of the same type in the second schedule A method comprising a communication time slot and a non-overlapping stage. The first base station-access terminal communication time slot, the first relay station-access terminal communication time slot, and the first base station-relay station communication time slot are different time slots that do not overlap,
Said method comprises
The method of claim 1, further comprising: determining the second schedule from an identifier corresponding to the second access point and stored schedule information.   3. The method according to claim 2, wherein the first and second access points are adjacent relay stations. 3. The method of claim 2, wherein the first and second schedules are the same but are offset in time from each other by two communication time slots . Located at a position where the second access point is adjacent to the sector of the second base station using the second schedule, each of said first and second base station of claim 3 comprising an odd number of sectors Method. Communicating with the first access point in accordance with a first schedule for use by the first access point, adjacent to the first sector of the first base station that includes the N sectors first access point is directed in different directions The first base station controls transmissions from the N sectors of the first base station using less than N schedules, and the first schedule is less than N schedules The first schedule is used to control transmissions from at least two adjacent sectors of the first base station , and the first schedule is a first base station-access terminal communication time slot, 1 relay station-access terminal communication time slot, including a first base station-relay station communication time slot, a first communication time slot repeating periodic sequence ,
Performing a handoff to a second access point synchronized with the first access point;
Communication with the second access point according to a second schedule that is used by the second access point, wherein the second schedule RS2 - access terminal communications time slots, the second base station - repeater station communication time slot, the second A second communication time slot comprising a base station-access terminal communication time slot repeating periodic sequence , wherein at least some of the communication time slots in the first schedule are the same type of communication time slots in the second schedule and At least one processor configured not to overlap ,
An access terminal comprising a memory coupled to the at least one processor. The at least one processor further comprises:
7. The access terminal according to claim 6, wherein the access terminal is configured to determine the second schedule from an identifier corresponding to the second access point and stored schedule information. The first and second access points are adjacent relay stations ;
8. The access terminal according to claim 7, wherein each of the first and second base stations includes an odd number of sectors . 8. The access terminal according to claim 7, wherein the first and second schedules are the same but are offset in time from each other by two communication time slots . And means for communicating with said first access point in accordance with a first schedule for use by the first access point, first the first base station including the first N pieces of sector access point is directed in different directions Located in a location adjacent to a sector, the first base station uses less than N schedules to control transmissions from the N sectors of the first base station, and the first schedule is less than N The first schedule is used to control transmissions from at least two adjacent sectors of the first base station , and the first schedule is a first base station-access terminal communication Means including a first communication time slot repeating periodic sequence including a time slot, a first relay station-access terminal communication time slot, a first base station-relay station communication time slot ;
Means for performing a handoff to a second access point that is synchronized with the first access point;
And means for communicating with said second access point according to a second schedule that is used by the second access point, wherein the second schedule RS2 - access terminal communications time slots, the second base station - repeater station communication time A second communication station comprising a slot, a second base station-access terminal communication time slot, and a repeating periodic sequence , wherein at least some communication time slots in the first schedule are of the same type in the second schedule An access terminal comprising means for not overlapping with a communication time slot .   11. The access terminal according to claim 10, further comprising means for determining the second schedule from an identifier corresponding to the second access point and stored schedule information. The first and second access points are adjacent relay stations ;
12. The access terminal according to claim 11, wherein each of the first and second base stations includes an odd number of sectors . 12. The access terminal according to claim 11, wherein the first and second schedules are the same but are offset in time from each other by two communication time slots . 13. The access terminal according to claim 12 , wherein the second access point exists in a position adjacent to a sector of a second base station that uses the second schedule . A computer program used in an access terminal,
At least one computer, a code for communicating with the first access point in accordance with a first schedule for use by the first access point, first including the N sectors first access point was directed in different directions Present in a position adjacent to the first sector of one base station, the first base station controlling transmission from the N sectors of the first base station using a schedule of less than N, and 1 schedule is one of less than N schedule, said first schedule is used to control the transmission from at least two adjacent sectors of the first base station, the first schedule is first 1st communication time slot repetition periodic system including base station-access terminal communication time slot, 1st relay station-access terminal communication time slot, 1st base station-relay station communication time slot And code, including cans,
Code for causing the at least one computer to perform a handoff to a second access point synchronized with the first access point;
Wherein at least one computer, a code for communicating with said second access point according to a second schedule that is used by the second access point, wherein the second schedule RS2 - access terminal communications time slots, the second A second communication time slot including a base station-relay station communication time slot, a second base station-access terminal communication time slot, and a repeating periodic sequence , wherein at least some communication time slots in the first schedule are A computer program that includes the same type of communication time slots in two schedules and non-overlapping code.

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